Intel RST RAID performance.

I suggest that you write a article about the performance of the Intel Rapid storage system with a RAID5 array. On the intel website you get the impression that it will perform really well. It does when it comes to read speed but write speed is extremelly slow and is for all intents and purposes useless. The Intel forums are full of people trying to get an answer out of Intel but to no avail.

I am used to installing and setting up RAID-systems and recently installed a RAID5 system with 6 disks on a brand new p67 motherboard. Installation and the setup was very easy and actually better than many other RAID-competitors (3ware,LSI, Adaptec etc).

My biggest gripe by far concerning Intel Rapid Storage Technology is the abyssmal write performance on RAID5!

I am aware of the problem with alignment issues affecting performance and hence use 512k sector drives (2TB Hitachi 7k3000). Write cache is enabled etc.

With this setup I am currently getting around 450-490 MB/s read speed which is great, however my write speed is around 30-40 MB/s?!

I have 16GB of RAM, a 2600K running at 4,5 Ghz and I would assume that this could perform the parity calculations needed for writing?

When performing write tests the CPU never goes above 10% so it is not lack of computing power.

This is about a third of the write speed of a single harddrive?! When searching this forum and looking on some other tests on the internet other users seem to be getting between 5-80 MB/s write speed (depending on the number and type of drives).

This is totally subpar and not at all acceptable, how can Intel boasts about all the advantages of Rapid Storage Technology with this beeing the reality of RAID5 performance?!

Nowhere on the site are there any performance figures quoted, the reason for this is quite obvious.

Also apparently the RAID10 implementation is inferior too (due to them not optimizing how they write and read from the striped drives within each set).

Most people respond to these posts that you should get a hardware raidcard. I have however done that several times before but was curious after reading all the marketing stuff on the website. If Intel can not deliver acceptable RAID5 write performance it should state that on the website so people do not have to waste time installing this crap and beeing dissappointed. This really drags down my impression of Intel as a serious actor in the storage business. Be honest and clear Intel, people will always appreciate that. Look for instance at what OCZ is doing in regards to their SSD-drives. My company will by OCZ SSDs from now on. State on the website that RAID5 write performance will be really low and if that is needed Intel Rapid Storage is not suitable.

Read speed seems to be on par with what I see from my highend controllers so if you are mostly contrained by readspeed Rapid Storage is great.

The reason it is slow is not due to lack of CPU horespower to calculate paritydata rather a really shoddy implementation.


Regards.

Thanks for the suggestion. I'll definitely pass it on.